[PATCH v2] lsm: check size of writes

[Tetsuo Handa]

On 2024/12/19 6:51, Paul Moore wrote:
> On Tue, Dec 17, 2024 at 1:27 PM Leo Stone <leocstone at gmail.com> wrote:
>>
>> syzbot attempts to write a buffer with a large size to a sysfs entry
>> with writes handled by handle_policy_update(), triggering a warning
>> in kmalloc.
>>
>> Check the size specified for write buffers before allocating.
>>
>> Reported-by: syzbot+4eb7a741b3216020043a at syzkaller.appspotmail.com
>> Closes: https://syzkaller.appspot.com/bug?extid=4eb7a741b3216020043a
>> Signed-off-by: Leo Stone <leocstone at gmail.com>
>> ---
>> v2: Make the check in handle_policy_update() to also cover
>> safesetid_uid_file_write(). Thanks for your feedback.
>> v1: https://lore.kernel.org/all/20241216030213.246804-2-leocstone@gmail.com/
>> ---
>>  security/safesetid/securityfs.c | 3 +++
>>  1 file changed, 3 insertions(+)
> 
> Looks okay to me.  Micah, are you planning to merge this patch, or
> would you like me to take it via the LSM tree?
> 
> Reviewed-by: Paul Moore <paul at paul-moore.com>
> 
> I'm going to tag this to come back to it in a week or so in case we
> don't hear from Micah, but if you don't see any further replies Leo,
> feel free to send a gentle nudge ;)

FYI: I sent

https://lkml.kernel.org/r/014cd694-cc27-4a07-a34a-2ae95d744515@I-love.SAKURA.ne.jp

which makes this patch redundant if my patch is accepted.